Electric riveting apparatus



1 3 sheets-sheen -1`.

'(No Model.)

E E RIBS ELECTRIC RIVBTING APPARATUS.

Patented May 12, 1891.

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(No Model.) 3 Sheets-Sheet 2.

E. E. R11-11S. ELECTRIC RIVBTING APPARATUS. No. 452,042. Patented'May12, 1891.

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` E. E. ms. ELECTRIC RIVETING APPARATUS.

No. 452,042. Patented May 12v, 1891.

Avlllllll-IIIIII WITNESSESB lNvlannoR:v En@ E 22W/ UNITED STATES PATENTOEEICE.

ELIAS E. RIES, OF BALTIMORE, MARYLAND, ASSIGNOR TO RIES d: HENDER- SON,OE SAME PLACE.

ELECTRIC RIVETING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 452,042, dated May 12,1891.

vApplication filed June 25, 1889. Serial No. 315,473. (No model.)

To @ZZ whom t may concern: forming two brackets 2 3, one above theother,

Be it known that I, ELIAS E. RIES, a citizen to support a rivetingmechanism composed of of the United States, and a resident of Baltiananvil and heading-die, hereinafter referred 1nore,in the State ofMaryland, have invented to. The bar 1 constitutes the secondary con- 5 5certain new and useful Improvements in ductor of an inductionaltransformer, the pri- Electric Riveting Apparatus, of which the marycoil 4 of which is composed of line wire,

following is a specification. which is placed parallel with and againstthe My invention has reference to machines or bar 1. The primary coil isbent into a loop apparatus'for riveting by the aid of elecbetween thetwo brackets 2 3, as shown, so as 6o Io tricity in themanner set forthin my applito leave additional room for the Work, which cation, No.285,555, filed September 15, 1888, latter is shown in the form of twoplates 5 6 and claimed in my application, No. 293,069, to be rivetedtogether. A shell or shield 7, of

filed December 10, 1888, and also in my patmagnetic material, andcomposed of two simid. ent, No. 403,374, dated May 1l, 1889; and the larcast-ings, (one only being showin) which are 65 object of the presentinvention is to provide provided on the inner end and outer edgesimproved practical means by which the elecwith iianges'7,through whichpass bolts S for trical riveting process may be effected with securingthe two castings together, iucloses ease and dispatch. the circularportion of both the primary and i The invention may assume a greatvariety secondary of the transformer, and serves to 7o zo of forms, andwhile I have shown in the drawconcentrate the magnetic lines of forcewithin ings forming part of this specification certhe transformer andthereby increases its effitain organized machines embodying theinciency. The shell sections are provided with vention, I am in noAmanner confined to the ears f), projecting from the outer flanges 7,foridentical construction shown. All this will attaching thetransformerto asuitable frame 75 more fully appear from the following detail or forsupporting itin any desired position. description with reference to theaccompany- If found desirable, the rigidity of the transing drawings, inwhichformer may be increased by a tie-rod 10. (In- Eigure 1 is a sideelevation of one form of dicated in dotted lines.) The bracket 2supriveting-machine embodying my invention, ports a heading die or tool11, which in this 8o zo in which a generator or inductionaltransinstance consists of a bolt with a threaded former forms anintegral part of the frame shank extending through a suitable nut in ofthe machine. Fig. lbisaside elevation of the said bracket, and ahand-wheel 12 or another form of riveting-machine embodying othersuitable device, whereby the bolt may features of my invention.Fig.2isaside elebe turned and thus elevated or depressed. 85

vation, with parts in section, of still another The lower end of the dieis frusto-conical in form of riveting-machine embodying features shape,as shown at 13, and has a cavity of of myinvention and designed moreespecially suitable shape formed in its face to receive for large work.Fig. 3 is a front view of the and mold the free end of the rivet-shank.

anvil and its supporting-bracket shown in The bracket 3 carries ananvil, which, as 9o 4o Fig. 1:1. Fig. et is an enlarged front view,shown in Figs. 1*l and 3,cousists of a block or partly in section, ofthe anvil and headingbody 14C, having an expanded upper end or die withadjacent parts shown in Fig. 1b, and head 15 with a broad 'flat face,inwhich is a Fig. 5 is a section on the line of the headcavity to receiveor mold the head on one ing-die shown in 4. end of the rivet, and on thesaid face is a 95 Like numerals of reference indicate like layer 17 ofinsulating material, not, howparts throughout all the drawings. ever,extending into the cavity provided l Referring more particularly toFigl, there for the reception of the rivet-blank head.

l is shown a heavy bar l, of copper or other This facing may be made ofasbestus cloth, good conductor of electricity, bent to a cirsoapstone,obsidian, agate, mica, or other in- 10o 5o cular shape, as indicated bydotted lines, with sulating and refractory substance. Extendthe freeends turned outward and parallel, ing through a nutin the bracket 3 isascrewthreaded rod 16, with its upper end engaging the under side ol. thebody lll of the anvil and supporting the latter. The rod 1G is turned bymeans of a hand-wheel 17 on its 5 lower end to elevate or lower theanvil. On the body 14 of the anvil are depending side wings 15',straddling the bracket 3 to prevent the said body from turning whenmoved by the rod 16. 1t will be understood, howro ever, that other formsof die and anvil and means for adjusting and actuating' themsuch, forinstance, as shown and hereinafter described in connection with theother iigures of the drawings-may be used. Depend- I5 ing from thebracket 2 are fixed legs 1G at the sides of the heading-die, andprovided at their lower ends with insulating material 17 of the kinddescribed with reference to the facing 17. If nowT the plates to beriveted zo together be placed on the head 15 of the anvil with the shankof a rivet-blank in the rivet-holes in the plates and its head in thecavity in the anvil, then the anvil may be elevated by manipulating thescrew-rod 1G 2 5 until the said plates are clamped between the expandedhead 15 of said anvil and the legs 16 depending from the bracket 2. Thefine-wire primary coil 4t receives alternating high-tension electricalcurrents by wires 1S 3o 18 from asuitable source-suoli as a dynamoconnecting with conductors 19 19. One wire 18 includes a suitablecurrent-regulator within easy reach, and, as shown, this regulator is areaction rheostat composed of a series of resistance-coils 20, a seriesof contact-plates 21, to which the terminals of the coils are connected,a soft-iron core 22 within the coils, and a switch-lever 23 arranged tomake contact with the plates 2l and with an idle con- 4o tact-plate 24.rlhe wire 18 is connected with the switch-lever and a continuation 1S ofsaid wire leading to the coil 4C is connected to the end plate of theseries of contactplates 21.

The operation of riveting with a machine constructed as shown in Fig. 1nwill now be understood. A rivet 25 is placed with its head, or, if therebe no head, with one end of its shank, in the cavity in the face of thean- 5o vil, and the shank itself engaging the rivetholes in the plates 56. The operator then manipulates the rod 16 to elevate the anvil,together with the plates and rivet thereon, until the said plates areclamped against. the lower ends of the legs 1G and held firmly theretoduring the entire operation of riveting. The heading-die is then screweddownward until in contact with the upper or free end of the rivet-shank,and the switch-lever 6o of the current-regulator is turned from the idlecontact-plate onto the other plates, and from one to the other of thelatter until the requisite current is passed through the rivet to bringit to the desired degree of incandes- 6 5 cence, as fully explained inmy aforesaid applications, after which the heading-die is furtherdepressed to upset the softened end of the rivet-shank and form a headthereon, which is molded by the cavity in said die. The current may bemaintained throughout the riveting operation, or it may be regulated asdesired, or be turned off at any time during` the operation of riveting,as the character of the work may require. A

In the machine thus far described the frame-work constitutes theproximate source of the heating-current, being, in fact, an inductionaltransformer, the induced or secondary circuit of which is composed of asingle heavv bar ot' copper' or other good conductor of heat andelectricity. The machine may thus be transported and set up at any placewithout in any way or manner disturbing its electrical connections,except that the two feeding-conductors 18 18 must be disconnected fromand then again connected with the main charging-circuit 19 19. Inaddition to this advantage, there is the further advantage of utilizing'the material unavoidably used for the frame-work of the machine for theimportant purpose of transforming the currents of high tension furnishedbythe primary source-such as a dynamo-into cu rients. of the requisitelow tension. After the riveting operation has been repeated a number oftimes the heading-die and anvil become heated, partially from thepassage of the heating-current through their contiguous ends andpartially from contact with the incandescent'rivets. The heating of thedie and anvil is very objectionable and renders theV operation ofriveting inconvenient and uncomfortable, and to overcome thisobjectionable feature I apply acooling medium to the said die or anvil,or to both of them, in any suitable manner. In Fig. l lthere is shown apipe 2G, leading from a source of cold-airsupply, (not shown,) andprovided with a nozzle 27, constructed to direct an air-jet against thelower end of the heading-die; and there is also shown another pipe 26',leading from the same source of air-supply and provided with a nozzle 27for directing an airjet against the upper end or head of the anvil. Itwill be understood that l am in no manner confined to the use ofair-jets for cooling the heading-die or anvil, and in lieu thereof l mayuse such means as are hereinafter described in relation to other Jformsof riveting-machines, or l may use any other means for the purpose,since my invention in this particular is designed to prevent undueheating of the heading-die or anvil.

Referring now more particularly to Fig. 1", together with Figs. 4 and 5of the drawings, there is shown a casting 2S, provided with projectingarms or brackets 2, 3, and 29, one above the other. The arm 3 carries ananvil 14, similar to the anvil shown and described in relation to Fig.1-`-that is, it has an eX- panded head l5, with an insulatiiig-facing`17 and a cavity for receiving a rivet-head, depending side wings 15straddling the bracket 3, and an adjusting screw-rod 1U,

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erate temperature during the operation of lwith its hand-wheel 17 forraising and lowering the anvil. In the present instance, however, theanvil is insulated from its support by a bushing 30 of insulatingmaterial seated in the bracket 3, and through a nut in said bushing thescrew-rod v16 extends, andthe inner faces of the wings 15 are coveredwith insulating material, as indicated by heavy lines. The anvil isprovided below the head l5 with a perforation for the reception of theend of a conductor 31, and a set-screw 32 entering said perforationserves to bind the conductor firmly in the said perforation in theanvil. As stated before with reference to Fig. l, any suitable means maybe employed to cool the anvil during the operation of riveting, and inthe apparatus shown in Fig. lb the anvil is provided for this purposewith two perforations 30, connected together at one end by acoupling-pipe 3l and at the other end connected, respectively, to aninlet-pipe 32 and an outlet-pipe 33. A cooling agentsuch as water orammonia-coming from a reservoir not shown, is made to Iiow through thepipe 32', from whence it will pass through one of the perforations 30',and by means of the coupling 3l to the other perforation 30', from whichit will escape through the pipe 33. The cooling agent will absorb heatfrom the anvil and will maintain the latter at a modriveting. The arm orbracket 2 serves as a guide for a reciprocating heading-die 33, reducedat its lower end to a frusto-conical form, and there provided with acavity for molding a rivet-head similar in this respect to theheading-die Il shown in Fig. l, and at the upper end the heading-die isattached to one link of a toggle 34, the other link of which is pivotedto the arm or bracket 29 of the casting 28. vThe toggle is connected foroperation with a piston-rod 35, driven by a suitable piston within acylinder 36, formed in the casting 2S. Steam or compressed air isadmitted to the cylinder through a pipe 37, having a valve 38 of thefamiliar globe type, and provided with a hand-Wheel 39. In the pipe 37,between the cylinder and the valve 38, is another valve 40, constructedto admit stealn'in front of or behind the piston when. actuated by avalve-rod 4l. Depending from and secured to the bracket 2 by bolts orscrews 42 is a jacket 43 surrounding and inclosing a portion of theheading-die, and having a perforation in the bottom through which thedie passes, and at which point the jacket is provided with a gasket 44to form a iiuidtight connection between the said jacket and die at theperforation. A cooling agentsuch as water or ammonia-is introducedintothe jacket bv means of asupply-pipe 45 coming from a reservoir or pump(not shown) and entering the jacket near the bottom, and aftercirculating around the portion of the die inclosed by the jacket thefiuid escapes through va pipe 46, from which it is returned to the saidreservoir or pump or is allowed to waste.

ration for the end of a conductor 47, which is held therein by aset-screw 48. Embracing the lower end of the heading-die are twolaterally-curved legs 49, having their lower edges coated withinsulating material 50. These legs do not entirely encircle the die,there being a space between their opposing edges for the passage of theconductor 47, as clearly shown in Fig. 5, and the said legs extenddownward from the bottom of the jacket 43, being either integraltherewith, as shown, or attached thereto in any suitable manner. Thecasting` 2S, together with the anvil and die carried thereby, is securedon the top of a suitable table 5l, one of the end supports or legs'52 ofwhich are shown. Supported between the legs of the table is aninductional transformer 53, from the thick-wire secondary coil of whichextend the conductors 3l and 47, and the fine-wire primary coil of thetransformer receives the current from the derived circuit-wires 54 54,leading from the main dynamo-circuit 19, or in any other suitablemanner. One of the wires 54 includes a current-regulator, which lnay beidentical with that shown in Fig. l, and is supported by a plate 55,depending from the end of the table 51. On the face of this plate ismounted the switch-lever 23 and the series of contact-plates 2l, whichlatter are connected with resistance-coils mounted on the inner face ofthe plate 55 and hidden from View thereby. The regulator isprovided\with an idle contact-plate 24, and the lever 23 andcontactplates 2l are in circuit with one of the feeding-Wires 54 and itscontinuation 54', leading to the transformer, respectively. Bindingposts56 on the leg 52 and plate 55, and forming the terminals of theregulator and one of the terminals of the transformer, are provided forconvenience in attaching the feedingwires. Below the transformer andwithin con,- venient reach is a pedal 57, pivoted at one end between thelegs 52 of the table 5l in any suitable manner, (not shown,) and at theother or free end provided with a step 58. This pedal is connected tothe valve-rod 4l, controlling the valve 40, and is held normallyelevated by a spring 59, attached to some fixed portion of the frame ofthe machine. Then the treadle is elevated, the valve 40 is in a positionto admit steam in front of the piston, in which case the toggle will beactuated to elevate the heading-die, and when the treadle is depressedthe valve 40 is moved to admit steam behind the piston, in which casethe IOO IIO

xmy aforesaid applications and patent.

toggle will be actuated to depress the heading-die.

The operation of the machine shown in Fig. lb will now be understood.The plates 5 6 to be riveted together, with the rivet-blank in position,are placed on the anvil and elevated with the same by turning thehand-wheel 17 until clamped against the lower insulated ends of the legs49 in the same manner hereinhefore described with reference to theoperation of the machine shown in Fig. lftof the drawings. The treadleis now slightly depressed and moves the valve 40 in a direction to admitsufficient steam or compressed air behind the piston to actuate thetoggle and depress the heading-die until in contact with the free end ofthe rivet-blank. The circuit now being completed through the secondarycoil of the transformer, conductors 3l and 47, the anvil, heading-die,and rivet-blank, the circuit through the primary coil of the saidtransformer being preferably maintained closed, a heating current ofelectricity is passed through the rivet-blank in the manner hereinbeforedescribed, and also described in lVhen the rivet-blank has been raisedto the desired temperature or degree of incandescence, the treadle 57 isfurther depressed to admit more steam behindthe piston, so as toforcibly move the heading-die down upon the softened rivetblank andupset the latter, the cavity in the die molding a head on the end ofsaid blank, while at the same time the shank of the rivet is upset tocompletely tillthe rivet-holesin the plates 5 and 6, the entireoperation being usually completed by one stroke of the die. If theheading of the rivet is not completed by such operation, the die may beraised and again forcibly depressed by a suitable manipulation of thetreadle, and repeated, if necessary, until the heading of the rivet issatisfactorily accomplished. During the operation the current may beregulated, as hereinbefore stated, or the current may be discontinued bymoving the switch-lever to the dead-contact, or in any other desirablemanner. As stated above, the circuit through the primary coil ispreferably maintained always closed through the coils of the regulator.Current begins to iiow through the rivet the moment contact is completedwith the dies, and the secondary current is then increased by moving theswitch-lever to cut out the regulator-coils, thus reducing the counterelectro-motive force generated thereby and permitting more current toilow through the primary coil, which, of course, increases the currentin the secondary. The regulating-switch may also be set to a certainpoint for given-sized rivets and the entire heating operation be left toitself. As the ends of the rivets make better contact with the dies asthey assume the proper shape, the resistance is gradually diminished andthe current automatically increased.

Referring now more particularly to Fig. 2 of the drawings, there isshown a riveting-machine adapted for heavy work, such as rivetingsteam-boiler plates and the like. There is a heavy U-shaped frame GO,with legs Gl 62, normally extending in a horizontal position, and thisframe is suspended by chains G3, secured to the upper leg 6l, andpassing around pulleys Gi, mounted in a truck-frame G5, from whence thechains are returned to winding drums or windlasses 6G, journaled betweenstandards 67, rising from the said upper leg (il. of the frame GO. Eachdrum is rotated by means of a crank GS on one of the ends of thedrum-shaft 69, and is held against a reverse movement by a ratchet-wheelon the said drum-shaft, and a pawl 7l on the adjacent standard 67. Thetruck-frame G5 has the pulleys Gi mounted on its under side near theends, and directly above said pulleys and on the upper side of the frameare mounted truck-wh eels 7 2, constructed to move on a rail or rails 73. Chains 74 are attached to the ends of the truck-frame 65 and extendto some convenient point where power may be applied to move thetruck-frame, together with the frame 60, along the track in eitherdirection to the desired position.

It will be understood that the drums G6 may be manipulated to raise orlower the frame G0 or incline it to any desired angle within thevertical plane marked by the chains 63 and by the two legs of the frameGO. To the free end of the lower leg 62 is secured a bracket 75,carrying a cylinder 76, in which is a piston 77, fitted forreciprocation therein. The piston is actuated by steam or compressed airadmitted through a pipe 78 into a valve-chamber 79, from whence it isdirected above or below the piston by a slide-valve 80, controlled by avalve-rod 8l, which may be manipulated by hand or otherwise. Thecylinder, together with the piston and means for admitting steam to thecylinder, being` of common and wellknown construction, no furtherdescription thereof is necessary. The anvil l-l in this machine iscylindrical in form and constitutes the piston-rod entering the cylinder7G through a stuliing-box 82, and at its lower end being reduced andpassed through the piston and clamped thereto by a nut S3, which latteris screwed onto the lower end of the anvil-stein, which isscrew-threaded, as shown, for the purpose. The anvil is insulated fromthe frame 60 by a bushing 84 of insulating material interposed betweenthe reduced end of the anvil and the piston through which it passes, andby another bushing of insulating material, which may also serve aspacking surrounding the anvilstem where it passes through thestufingbox. The upper end of the anvil has formed on it an expanded headl5', having a facing 17 of insulating material and a cavity for the heador end of a rivet-blank, similar to and for the same purpose ashereinbefore described with reference to the anvils shown in Figs. l and1b. Below the head 15 the anvil is provided with a perforation for therecep- IOC tion of the end of a conductor 86, leading from a source ofelectricity capable of producing a low-tension current of greatquantity, and which may be a transformer similar to either of thoseshown in Figs. 1 and 1b, or of any other suitable form, or a suitabledynamo or secondary battery. The conductor is clamped to the anvil by aset-screw S7 entering the aforesaid perforation in the anvil. To thefree end of the upper legs 61 of the frame 60 is secured a bracket Se,having an upwardly and a downwardly projecting arm 89 and 90,respectively. The arm S9 of the bracket 88 carries a steam-cylinder 91,constructed to cause the automatic reciprocation of a steam-hammer 92,forming the piston and piston-rod, when steam or compressed air isadmitted to the cylinder 19 through a pipe 93.

It is not necessary to describe in detail the construction of thesteam-hammer, since the same forms no necessary part of my invention,`for the purposes of which it is of no consequence how this steam-hammeris constructed, so long` as it is reciprocated under the action of thesteam or compressed airadmitted by the pipe 7 8. I have therefore shownin the drawings a steam-hammer of ordinary construction, which may bechanged in various ways without affecting the principle of operationwhich forms the basis of my invention. The steam-hammercylinder91 isprovided with a neck 94, through which extends the rod 95, forming apart of the hammer, and the free end of which constitutes thehammer-head. The arm of the bracket SS is provided with a horizontalextension 96, having a vertical passage for a heading-die 97, the latterconsisting of a cylindrical b ody reduced at the lower end to atruste-conical shape and there provided with a head-molding cavity,(indicated by dotted lines,) and at the upper end, above theextension96, the said die is provided with a buffer 98, of rawhide or othernoise-deadening material, in line with the head of the hammer 92. Belowthe buffer 98 the die is encircled by a collar orange 99, against thetop of which bears the lower end of a coiled spring 100, encircling` thesaid die and bearing at its upper end against the lower end of the neck9a, the said spring tending at all times to depress the die. Projectingfrom one side of the die, near its lower end, is a pin 101, extendingthrough a slot 102 in the side of the extension 96 of the bracket-arm 90and in the path of the shorter arm 103 of an angle-lever lOl, pivoted tothe said arm 90, and constructed to be manipulated byhand. The lever104; is held with its shorter arnl in a normally-depressed position by aretractile spring 105, as shown. 1t will be evident that when the longerarm of the lever is depressed the shorter arm will be raised, and,acting` upon the pin 101, will elevate the heading-die against theaction of the spring and above the' position shown in the drawings.Depending from the extension 96 of the bracket-arm 90 are two legs 106,each with a facing. 107 of insulating material on their lower ends.These arms constitute the lixed member of a clamp, the movable memberbeing the anvil before described, and it will now be understood that twoplates 5 6 to be riveted together may be placed over the anvil with arivet-blank in place in matched rivet-holes in the said plates, and thatsteam or compressed air may be introduced into the cylinder 76 below thepiston 77, when the anvil will be raised and force the said platesagainst the insulated lower ends of the legs 106, and thereby clamp themfirmly together between the said anvil and legs. A conductor 108,leading from a transformer or other source of electric energy from whichthe conductor 86, before mentioned, leads, is connected to the upper leg61 by a set-screw 109, or otherwise. To insure good electric connectionbetween the movable heading-die and the portion of the bracket SSthrough which it is passed, and which is in circuit with the conductor10S, there are contact-brushes 110, secured to the bracketextension 96at the sides of the heading-die, and bearing at their free endsdirectlyon the said heading-die, so as to have a sliding contacttherewith when the heading-die is moved in a longitudinal direction.

The operation of a riveting-machine constructed as shown and describedwith reference to Fig. 2 is as follows: The entire apparatus is iirstadjusted by means of the supporting-truck and the windlasses, in themanner before described, until the anvil is below matched rivet-holes inthe plates in which a rivet-blank is inserted. 'lhe heading-die is thenelevated by manipulating the lever lOl, after which steam or compressedair is admitted into the cylinder 7 6,below the piston 77, and the anvilis r ised, thereby clamping the plates firmly against the insulatedlower ends of the legs 106. The lever 10% is now moved to its normalposition and the heading-die is forced downward by the spring 100 intointimate contact with the upper or projecting end of the rivet-blank.Vhen the parts are in the position just described, there is an electricconnection from the conductor S6 to and through the anvil, rivet, andheading-die, and by the contact-brushes 110 tothe upper leg 61 and theconductor 10S. The current is new turned on and controlled by a suitableregulator, (not shown.) which may be constructed in the same manner asthose described with reference to Figs. 1 1b, unt-i1 the rivet is heatedto the desired state of incandescence. Steam or compressed air is nowadmitted through the pipe 92S to the cylinder 91, the hammer isautomatically reciprocated in a manner well understood, and a rapidsuccession of heavy blows is struck on the upper end of the heading-die,thus upsetting the softened rivet-blank and forming a head thereon. lnorder to maintain the heading-die and anvil at an approximately normalIOC IIO

temperature, air-jets are directed against them by pipes 26 2U',respectively, which may be similar to those described with reference toFig. l1 of the drawings, and are provided with nozzles adjacent to thesaid die and anvil; but I may use any other suitable means for thepurpose of cooling the anvil and die, and I am, therefore, not confinedto the use of airjets in connection with the machine illustrated in Fig.2.

It will be observed that in each machine hereinbefore described the faceof the anvil and the lower ends of the legs, forming the two members ofthe clamp for holding the plates together, are shown with a facing ofinsulating material, which, however, may be applied directly to theplates around thel rivetholes, a coating of mineral paint or othersimilar substance giving good results. By this means the current passingbetween the anvil and heading-die is con lined to the rivet, and theplates, therefore, remain comparatively cold during the operation ofriveting, and are not compressed or distorted when the rivetblank isupset.

In the use of the different forms of apparatus hereinbefore described,the anvil and heading-die, being used at the same time as the terminalsof the circuit-carrying current of great quantity for heating the rivet,are themselves readily heated, and unless provision were made forcooling these dies and anvils they would soon soften to such an extentas to render their continued use impracticable. For this reason theheat-abstracting or refrigerating` devices hereinbefore described areused; and it will be understood that I am not at all confined to the useof the refrigerators shown in this case, since any other means forabstracting the heat from the dies and anvils may be employed.

In order to prevent as much as possible the heating of and to morereadily abstract the heat from the working ends of the dies and anvils,the same are preferably made of a metal of high conductivity for bothheat and electricity, and especially, when possible, of greaterconductivity for heat and electricity than the rivets employed. If ironrivets are used, the working ends of the die and anvil may be made withadvantage of phosphorbronze, aluminium bronze, or any other suitablealloy of copper, and in all cases the crosssections of both the die andanvil are made much larger than that of the rivet.

Having now fully described my invention, I claim and desire to secure byLetters Patentl. In an electric riveting apparatus, the combination,with a heading-die, of an anvil adjustable to and from the die and anelectric circuit including said die and anvil, substantially asdescribed.

2. In an electric riveting apparatus, the combination, with aheading-die and anvil, of a clamp for the articles t0 be riveted and anelectric circuit including thesaid die andanvil, substantially asdescribed.

3. In an electric riveting apparatus, thev combination, with aheading-die, of. an anvil adjustable to and from the die, a clamp forthe articles to be riveted, one jaw of which clamp is formed by theanvil, and an electric circuit including said die and anvil,substantially as described.

4. In an electric riveting apparatus, the combination, withaheading-die, of a clamp for the articles to be riveted, one jaw of theclamp consisting of legs at the sides of the die, an anvil'adjustable toand from the die constituting the other jaw of the clamp, and anelectric 'circuit including said die and arnvil, substantially asdescribed.

5. In an electric riveting apparatus, the combination,with aheading-die, of an anvil, a clamp for the articles to be riveted, onejaw of which clamp is formed by the anvil, alayer of insulating materialinterposed between the working-faces of the clamp-jaws and the articlesclamped, and an electric circuit including the die and anvil,substantially as described.

(5. In an electric riveting apparatus, the combination, with aheading-die, of an anvil, a clamp for the articles to be riveted, onejaw of which is formed by the said anvil and provided with a layer ofinsulating material on the working face of each jaw, and an electriccircuit including the anvil and die, substantially as described.

7. In an electric riveting apparatus, the combination, with aheading-die and anvil forming the terminals of an electric circuit, of4a refrigerator for cooling said die and anvil, substantially asdescribed.

S. In an electric riveting apparatus, thel combination, with aheading-die and anvil forming the terminals of an electric circuit, ofpipes provided with nozzles for directing a cooling agent against theworking ends of said die and anvil, substantially as described.

tl. In a machine for heating metals electrically preparatory to shapingthe same, the combination of a ring-shaped bar constituting thesupporting-frame of the machine and also the secondary of an inductionaltransformer, with the primary of such transformer applied to said bar,and a shell or envelope of magnetic material for said transformer,substantially as described.

10. In an electric riveting apparatus, the combination, with aninductional transformer constituting the frame-work of the apparatus, ofan anvil and heading-die forming the terminals of the secondaryconductor of said transformer, substantially as described.

l1. In an electric riveting apparatus, the combination, with aninductional transformer constituting the frame-work of the apparatus,and consisting of a tine-wire primary coil and an open frame forming thesecondary conductor, of an anvil and heading-die forming IOO IIO

the terminals of said secondary conductor, substantially as described.

12. In an electric riveting apparatus, the combination, with aninductional transformer constituting the frame-work of the apparatus,and consisting of a tine-wire primary coil, an open frame forming thesecondary conductor, and a shell of magnetic material for the saidprimary and secondary, of a heading-die and anvil forming the terminalsof said secondary conductor, substantially as described.

13. In an electric riveting' apparatus, the combination, with aninductional transformer composed of a tine-wire primary coil and asecondary conductor with adjacent projecting ends, of an anvil andheading-die carried by said ends and a clamp for the articles to beriveted, one jaw of which is formed by said anvil, substantially asdescribed.

14. In an electric riveting` apparatus, the combination, with aninductional transformer constituting the frame of the apparatus andprovided with a secondary conductor having adjacent projecting ends, ofa heading-die and adjustable anvil carried by said ends and a clamp forthe articles to be riveted, one jaw of which is formed by the saidanvil, substantially as described.

15. In an electric riveting apparatus, a heading-die and anvilconstituting the terminals of au electric circuit, composed of an alloyof copper having higher specific conductivity than the metal of therivet operated upon, substantially as described.

16. In an electric riveting apparatus, the combination of a heading-dieand anvil composed of a metal of higher specific conductivity than thatof the rivet operated upon, with guides and supports for the anvil anddie, composed of a metal of inferior electric conductivity,substantially as described.

17. In an electric riveting' apparatus, aheading-die and anvil composedof aluminium bronze having higher specific conductivity than the metalof the rivet operated upon, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ELIAS E. RIES.

Witnesses:

JNO. T. MADDOX, LEOPOLD Bins.

